A promise I shall give you, my love
by TheUsagi1995
Summary: 1shot. The team is gathered around the desk and Magnus explains:'This isn't any greater demon. It's Lilith, the mother of all demons.' Magnus realizes the enemy they must fight is more powerful than any other adversary they have faced & fear for Alec's fate clunches around his heart. Alec sees what's happening and assureS him nothing bad will happen to them. ScaredMagnus. Malec.


_**Hi there! So, after watching the new trailer, I came up with a couple of ideas for different possible scenes. Here #1. Taking place in the office where Alec, Izzy, Simon, Clary and Magnus are gathered around the wooden desk. We see Magnus explaining that ''This isn't any greater demon. It's Lilith, the mother of all demons.'' Magnus fears for Alec and the archer must find a way to calm his lover down!**_

 _ **I am not really happy with what this turned out to be... I hope it's not that bad... Ps. I haven't read the books guys. So, when it comes to Lilith I improvised a little bit.**_

 _ **I do not own neither the books, nor the TV show, nor any of the characters. No money is made by this.**_  
 _ **Off we go!**_  
 _ **Hope that you'll enjoy! A/N!**_

 _ **FULL SUMMARY: Based on the new trailer for season 3 of Shadowhunters. Spoilers if you haven't seen it.**_

 _ **1shot. Magnus, Alec, Izzy, Clary and Simon are gathered around the desk and Magnus explains who they are fighting against: ''This isn't any greater demon. It's Lilith, the mother of all demons.'' The words escape his lips and all of a sudden, Magnus realizes, the enemy they must fight is more powerful than any other adversary they have ever faced. Fear clunches around Magnus' mind and heart then. Fear not for his own well being, but for Alec's fate. Alec sees what's happening and takes it upon himself to calm Magnus down and assure him nothing bad will happen to either of them...**_

 _ **Off we go!**_

* * *

 _ **"A promise I shall give you, my love..."**_

"This... This is not just any Greater Demon... This is Lilith, the mother of all demons..." The words left Magnus' lips slowly, and when they were finally out of his mouth, the man paused, swallowing thickly, before licking his dry lips. Next to him, Clary gasped in fear. Magnus let his eyes flutter closed. How was this possible? How was it, that Lilith was walking the Earth and was not locked up in the darkest pits of Edom, like she was supposed to? Magnus shook his head, trying to come up with an answer, but his mind was blank. Lilith... Lilith... The Warlock let the word echo in his mind as he took a few steps back and moved towards the door of the room. He could feel four pairs of eyes fixed on his back and knew that Izzy, Clary, Simon and most importantly, Alec, had turned their eyes on him.

* * *

They had come to him for help, waiting to hear words of wisdom, wanting to get a glimpse of the knowledge the High Warlock of Brooklyn had, when it came to Demons. For all they knew, Magnus had an answer to every problem. What they didn't know however, was that those who actually knew about Lilith were too few. The reason? For one, the Hellish creature had been locked up in Edom for centuries. And secondly, even if one was to meet her, the chances of surviving their encounter were scarce. "Magnus?" Clary's voice reached the Warlock's ears and got him back to the present. He was aware he had turned his back on the desk around which the quartet was gathered, but he needed a few seconds to regain his composure. "Magnus, what do you know about Lilith?" Clary pressed, when the Warlock remained silent.

* * *

What did he know? Magnus had heard rumors... During his long lifespan he had heard various creatures of the Downworld mutter a few hushed words about Lilith, the most powerful of all the Demons, the one who was capable of unleashing, Hell on Earth. Most of those who had dared to speak of her, had done it in a low voice, and their words were scarce, spoken under their breath. Even if Lilith wasn't walking the earth, her name was a cause of fear for Downworlders and Shadowhunters alike.

* * *

And they had every right to be afraid of her, Magnus thought, letting a small, ironic, smile push the edge of his lips upwards. 'They?' Oh, but who was he kidding? He was afraid of her as well. Because he, the High Warlock of Brooklyn, was the son of a Greater Demon. Said greater Demon was no other than the mighty, arrogant, Asmodeus, who had often spoken of the invincible Lilith, and in utter contradiction to every other story Magnus had ever heard, this one had been told loudly, and the words Asmodeus had spoken were bearing no sign of fear.

* * *

So, yes, Magnus knew more about Lilith than most, for he had heard more than scattered, muttered rumors. But little did that fact manage to calm his rapidly beating heart. Knowing your enemy, his tendencies and weaknesses, surely was an advantage, but when the one opposing you is Lilith, said advantage loses almost all meaning. Magnus pressed a hand on his knitted eyebrows, before turning around so as to face his friends. "Lilith is more powerful than any demon you have ever faced. She is almost impossible to kill, and the range of her powers extends beyond comprehension. She can and will, if given the chance, obliterate us all." The Warlock stated, steeling his voice so as to hide the fear which was lingering within his words.

* * *

"How do we stop her? What can we use against her? Izzy questioned in a low voice. "Your weapons can barely scratch this demonic entity, but even if you were in possession of a powerful weapon, capable of harming her, you would never get close enough to use it." Magnus elaborated, eyes flying open when Alec spoke, voice sure and steady. "I don't have to get close to her." The archer said, causing everyone around him to gasp in surprise as they realized what the young man meant. "He's right! Alec could hurt Lilith from afar-" "Haven't you been listening to what I have been saying, biscuit?" Magnus rasped, cutting Clary off, only to be interrupted by Simon a moment later.

* * *

"But that could actually work, if Alec were to shoot let's say a poisoned arrow or something-" "She would sense him. He wouldn't even manage to pass the arrow through the-" "Come on Magnus, Alec can surely move fast and he's very well trained!" Simon exclaimed in a rather happy voice, which made Magnus' stomach flip. A chill ran down his spine at the mere thought of his beloved Alexander, facing the mischievous demon. A tremor, which didn't go unnoticed by the young archer, whose breath hitched in his throat. "What is it Alec?" Izzy, who was standing next to him, asked, careful to maintain her voice low. "They have to leave. Now. I need to be alone with him." Alec replied in a hurry, eyes set on Magnus, whose frame went numb all of a sudden.

* * *

"But we have to find more about Lilith and besides, you two will be alone tonight-" "Izzy, this is important." Alec pressed, still eyeing Magnus, who, as the archer could tell from experience the others lacked, was lost in the depths of his own mind. Yes, he had seen Magnus getting lost in a labyrinth of his own memories once before, the time after Valentine had possessed his body. Magnus had taken a few steps backwards and had turned his back on Clary and Simon once again, eyeing his own image, as it was reflected in the window which was near the desk. But Alec wasn't sure the Warlock was seeing himself in the glass. In fact, he was certain that the one staring back at Magnus through the glass was a bloody, molded version of Alec, who had been utterly defeated by Lilith.

* * *

"Izzy..." Alec pleaded, taking his eyes from his boyfriend for only a moment. "Izzy, please..." He mumbled, and when his hazel eyes met Izabelle's black ones, the woman gasped as she beheld two shiny orbs filled with love and worry for Magnus. "Okay. Okay big brother..." The black haired Shadowhunter said, squeezing Alec's shoulder. Before the archer could count to ten, Izzy had come up with an excuse- something about an old book which could help them- and she was heading out of the office, with Clary and Simon right behind her. Once the door was shut, Alec blew out a long sigh and moved towards Magnus, who seemed totally lost. And lost he was indeed, trapped in his own mind, which had gotten ahead of itself, creating the vividest and scariest of images within seconds.

* * *

Simon's words got mixed with Magnus' own knowledge regarding Lilith, as well as with his fear of losing Alec, and before the Warlock could tell, he was being swallowed by a black hole, which was always lurking in the back of his mind, ready to devour every good and happy thought the Warlock had. Hellish images passed before sad, brown eyes, and Magnus was left at their mercy. In those images, Alec lay dying, mattering Magnus' name through gritted teeth... Magnus closed his eyes, longing for the images to be gone, but they stayed there, along with Alec's broken whispers of his name...

* * *

"Magnus..." A light squeeze on his shoulder was enough to oblige the Warlock to open his eyes once more. His frame shivered as Magnus came back to the present. Alec was standing next to him, searching his face for any sign of discomfort or pain. "Well, as I was saying..." Magnus' words died in his throat as he saw the room was now empty and Alec hurried to explain, offering the same excuse his sister had. Magnus was initially startled, but eventually resigned, letting his shoulders slump and his head fall, as he nestled closer to Alec.

* * *

"Hey..." Alec chanted sympathetically, face frowning when all the Warlock did, was to lower his head even more. "What are you thinking?" Alec questioned in a muttered voice. At the sound of these words, Magnus did raise his head, a look of surprise passing over his face, brushing the fear away, albeit momentarily. "I..." Magnus was startled once more, as he beheld the young archer's face softening. "I know you well enough to notice that you got lost in your head." Alec explained, allowing his lips to form a small smile, which was enough to brighten Magnus' world. Their eyes met then, and Magnus was sure he could drown in all the love these two bright orbs were holding.

* * *

"Magnus... What is it?" Alec questioned, eyeing his lover carefully. "Alexander... Lilith is no common Demon. A Vampire's speed and hearing both pale in comparison to hers. Her senses are always sharp, she can see in the dark... In fact, Lilith herself is a part of the darkness which spreads over the city." Magnus explained, feeling the words creeping inside him from the pores of his skin. He shivered and felt Alec nestling closer to him at once. "Mags, look-" "She is lethal, Alexander. She never shows mercy, she tortures and slays all who oppose her, she's-" Magnus stopped himself, biting his bottom lip to the point of drawing blood. His mind was aware of the fact that he was looking completely vulnerable and thus the Warlock tried his best to pull himself together. Only he didn't have the time.

* * *

"Hey... Magnus, it's going to be alright." Alec promised, pulling the man who was standing before him against his chest, before the Warlock could get the chance to turn around and away from him. "Alexander-" "It's alright, it's fine..." Alec muttered, as he tightened his hands around Magnus' slightly trembling shoulders. "As much as I want to be near you, Alexander, we have to find a way to approach Lilith-" "We will find a way Mags. We're going to find a way out of this, you and me both." Alec stated, cutting his lover off, crushing him on his broad chest even harder, stealing all breath from his lungs.

* * *

Magnus shivered anew at the sound of these words, and his furled hands tried to push his lover's body away, but to no avail. "Please... Magnus, please, don't push me away. Not again..." The young man pleaded, taking a step back so as to be able to look at Magnus. The Warlock's brown eyes widened and shone under the dim light of the office. It was in that moment, that Magnus felt something inside him had been broken. "Alexander... I'm scared..." The Warlock muttered at long last, letting his mask crack, for the one standing before him, was Alec. And Alec had always been there, would always be there.

* * *

"I know. I know Magnus." Alec replied softly, tapping his lover's chin upwards. "It's alright to be afraid. Fear is a powerful weapon if utilized correctly." The young Nephilim offered, in an attempt to ease Magnus' tensed body. "I'm not afraid of what will happen to me, Alexander." The Warlock stated, voice a little louder than before. "I know that too, Magnus." Alec explained, taking his lover's face in between his hands. "I know it, because I know you." The two lovers fell silent after that, for Magnus knew he could never ask his lover to stay away from Lilith, to stay away from a deadly fight, no matter how much he wished him to. He could never ask Alec to choose him, for Alec was a Nephilim. And Nephilim, would always, choose the world...

* * *

"I'm not afraid of what's going to happen to me, Alexander..." The Warlock muttered again, as if he was unable to say anything else. His hands moved at their on accord, and ring clad fingers grabbed fistfuls of Alec's black shirt. "I'm right here Magnus, right here." Alec chanted in a low voice, breathing in his lover's scent. Magnus shivered once more, causing Alec to move. "If anything were to happen to you, Alexander-" "Nothing will happen to me." Alec assured, but when Magnus stayed silent, the young man repeated his last phrase in earnest. "Nothing will happen to me..." Alec said, putting every bit of love he had, in those words.

* * *

Magnus' eyes shone and his breath hitched, as his frame started shaking anew. Alec licked his lips, raking his mind for a way to calm his lover down. After a few moments of stillness, Alec made his move, praying to the Angel that it would be the right one. "Hey..." the young man offered softly, letting his trained hands fall from the Warlock's face, only to take a hold of Magnus' shaky hands. Ring clad fingers felt cold in his grasp, so Alec brought their entwined hands close to his mouth, blowing out a hot breath.

* * *

"Hey, look at me..." The Nephilim asked in a low voice, waiting for the Warlock to meet his gaze. When he did, Alec spoke again. "I know it's bad. I can tell from what you've told us. But we'll deal with it. We defeated Valentine, so that's-" "I don't want to be rude, but that's nothing. Alexander... Lilith is one of the most powerful beings to ever walk this earth." Magnus uttered, his wavering voice making Alec nestle even closer to his lover's body. "We'll find a way, Magnus." The young man offered kindly. "Besides, Lilith may be all mighty and powerful, but we have you on our side. An all powerful Warlock, the High Warlock of Brooklyn. And that means a lot." Alec said, letting a small smile find its way to his lips.

* * *

Magnus was left staring at this courageous young man as if he was but a mirage, which would disappear the very next moment. A myriad of different emotions passed over Magnus' face one by one. Alec didn't have the time to catch them all, but what he did see- the surprise, the disbelief, the realization, the utter and complete devotion and last, but by no means least the unconditional love- made him blew out a long breath. He tightened his hands around Magnus' own, and then spoke, making sure his voice was steady.

* * *

"As long as you're here Mags, I know things will be fine. And I may not be able to promise you I won't go after Lilith at some point-" Here the archer locked his gaze with Magnus', urging him not to interrupt him. "...But I can, and I will promise you, that I will be careful." Alec concluded, tilting his head to the side, allowing Magnus to bury his face in the crook of his neck, which the Warlock did, without thinking about it.

* * *

"Promise me you'll be careful. Promise me, Alexander..." The man uttered, his words muffled by Alec's own skin, which Magnus' lips were brushing. "I promise Magnus. I promise you." The archer assured, body tensing for a moment when all of a sudden, Magnus' trained hands curled around his back, drawing him ever so close to the Warlock's body. It was a simple gesture, but Alec knew it meant so much more. 'I'll never push you away.' Was what Magnus had said without opening his mouth to speak. Alec returned the gesture in earnest, letting his hands form a cocoon around Magnus' broad shoulders.

* * *

They stayed like that for a long while, holding one another for dear life. Alec kept muttering reassurances in his lover's ear, until at some point, Magnus pulled his hands back and leaned forwards, capturing Alec's lips in a slow, yet desperate kiss, with which he was demanding, or maybe he was pleading, that his lover would not go back on his promise. As if Alec had read his mind, he took a step forward, crushing his lips on Magnus' even harder, pleading silently that the Warlock would not place himself in harm's way either. Because neither, could live without the other. Because neither, could push the other away. Because neither, could live in a world where the other didn't exist...

* * *

 _ **THE END...**_

* * *

 ** _So, here it ends! Loved it? Hated it? None of the above?_**  
 ** _I would love to hear your thoughts! Kudos and comments are always welcomed!_**

 ** _I am not really happy with what this turned out to be... I hope it's not that bad... Ps. I haven't read the books guys. So, when it comes to Lilith I improvised a little bit._**

 ** _I do not own neither the books, nor the TV show, nor any of the characters. No money is made by this._**

 ** _So, until next time,_**  
 ** _Love you all,_**  
 _ **Usagi!**_


End file.
